The KTM West Coast railway line runs from Padang Besar close to the Malaysia–Thailand border in Perlis (where it connects with the State Railway of Thailand) to the Woodlands Train Checkpoint in Singapore. It is called the West Coast railway line because it serves the West Coast states of Peninsular Malaysia. The line is owned and used entirely by Keretapi Tanah Melayu (KTM).
The 1,151-kilometre line is busier than the East Coast railway line because the West Coast railway line handles a variety of passenger train services such as the KTM ETS services, the KTM Intercity services, the International Express, the KTM Komuter in the Klang Valley and Greater Penang areas, and freight trains. Of this total length, 759 km is double-tracked and electrified.
The major stations on the line include KL Sentral in Kuala Lumpur, Butterworth in Penang and Johor Bahru Sentral in the south in Johor.